While the market is expecting Apple to ship between 5 and 10 million units in 2014, Kuo said in a recent investors note sent to Apple Insider that the company is only likely to ship 3 million watches.

This could result in "fewer units available" upon launch, as Apple Insider pointed out.

Apple may have trouble producing enough sapphire covers for the watch's screen. It's unclear if this is why Apple could be delaying its production of its smartwatch, but Kuo believes at least half of Apple's iWatches will use glass instead of sapphire to coat their displays. (This seems odd to us. Why would Apple do half-and-half?)

This follows another report from early July in which Kuo first reported that iWatch production would be pushed back to November. Kuo attributed this delay to "new challenges" in developing the hardware and software for the iWatch.

Apple has been rumored to enter the wearables market for more than a year. Re/code reported in June that the iWatch would debut in October, although newer reports make this seem less likely. Apple's first smartwatch is expected to focus on fitness in addition to delivering notifications, but we won't know for sure until Apple makes an official announcement. Some have even theorized that it could be Apple's gateway into mobile payments too.